Palaeontologists have discovered the fossil of a previously unknown species of lizard in mid-Cretaceous amber unearthed in northern Myanmar.
The newly discovered species was a small lizard, estimated to be about 3 centimetres (1.2 inches) long from snout to anus.
Named Electrosincus ZeddyIt lived during the mid-Cretaceous period, about 99 million years ago.
Unlike other squamate animals (lizards and snakes) that lived during the Mesozoic era, they have a layered and complex structure. Cortical bone They are arranged alternately around the body, supporting its classification as a lizard. Gerbils.
“The family Pectiniidae is a highly diverse lineage of squamate animals that is now nearly universally distributed in temperate and tropical regions around the world,” said Dr. Juan Daza of Sam Houston State University and colleagues.
“This comprises more than 1,745 described extant species, about 15 percent of all extant lizards.”
“Typically, lizards have cylindrical bodies and relatively short limbs, and evolution towards shortening or loss of limbs has occurred in more than 50 lizard lineages.”
“Among the living syncoids (Xanthus, Gerphosauridae, Cordylidae, and Syncoidae), syncoid species have the greatest range in body length, ranging from tiny species just a few centimetres in length to extinct species. Tiliqua FrangensIt may have reached a height of more than 50 centimetres.”
“Skinks also vary greatly in the number of presacral vertebrae, ranging from 26 to 108, which, together with round scales and compound bone plates, may have facilitated the repeated evolution of depressed and limbless morphologies.”
“Most lizards have smooth, circular scales beneath which extend compound osteoderms, which are bony plates within the dermis made up of multiple articulating dermal fragments per scale.”
One Burmese Amber (Burmit) Preservation Electrosincus Zeddy It was discovered in a Mid-Cretaceous outcrop about 100 km west of Myitkyina Township, Myitkyina District, Kachin State in northern Myanmar.
The specimen contains two separate parts of a lizard, including scales and mainly appendicular bones, but is clearly part of a single individual.
“To date, more than 100 squamate specimens have been discovered in Burmite,” the paleontologists said.
“Within this large sample, the new fossil is the only one that preserves this cortical bone morphology, which makes it diagnosable as a Snecidae and distinguishes it from all known fossil squamates from the Cretaceous.”
“Although the specimen is incomplete, it preserves both postcranial skeletal elements and integumentary structures, which, although less than ideal, provides a basis for comparison with putative synthid specimens that may be discovered in the future.”
“This specimen has a combination of compound bony plates and overlapping circular scales that are only seen in lizards.”
“We suggest that this type of osteoderm evolved as a response to increased scale overlap and reduced stiffness of the skin armour,” the researchers concluded.
Their paper Published in the journal Scientific Reports.
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JD Daza others2024. A compound osteoderm preserved in amber identifies it as the oldest known lizard. Scientific Reports 14, 15662; doi: 10.1038/s41598-024-66451-w
Source: www.sci.news